New year, new you, new do? After a quick stint in college as a blonde, I've been sporting my natural brunette hair color for over a decade. But I always stare in envy when I watch girls be bold and change it up. How do they know they'll like it? Hair color is a (semi)permanent decision, right? Meet Marie Robinson, Clairol's Color Director, who I caught up with in LA at the People's Choice Awards. With a client list that has included Anne Hathaway, Rachel McAdams, Emma Stone, Natalie Portman, Kristen Stewart and Naomi Watts, I knew I had to sit down and pick Marie's brain for celeb secrets that us gals can use at home.

Glamour: What are the rules of thumb to coloring your hair at home vs. in a salon?

Marie: The time when you can really do your hair at home is if you want to go darker, redder, or just a little bit lighter or golder, for more subtle changes. My rule of thumb is that if you are staying within two shade ranges of your natural color—going lighter or darker or redder—permanent color is an excellent option and you will get the results that they are showing you. If you are going more than two shades lighter or darker, see a professional. And then once you see a professional, they can tell you what to use at home to retouch.

Also, if you are going darker or redder at home, I would recommend to do it in stages. Don't start with the color on the box that you think you want to go. Pick the one that's at the halfway point, because that might be enough for you and not as shocking. And then you can always build on that without messing up.

Glamour: How do you choose the right color at the drugstore?

Marie: A really nice simple trick I like to tell people is__gauge it based on the jewelry you wear.__ If you're someone who can wear gold jewelry, you can probably wear reds and golds and caramels. If you're someone who looks better in silver jewelry or even cooler makeup, then generally a cooler hair color would look nice on you too. So look for tones that say "ash," "cool," or "beige." If you can wear a lot of rose gold, then your skin is probably more neutral, so you can wear a lot of different colors.

With all permanent hair color, usually the color on the box isn't the only representation of what that hair color is. On the side or back of the box, there are several different colors they will show you from where your starting color is to how the color is going to react on it. This is really important, because hair color will react differently based on what your natural color is.

Glamour: Can you talk us through the hair dye options out there? What's the difference between semi-perm, permanent, demi-perm?

Marie: Permanent is for anyone who has more than 25% grey. So if you're having more greys than you can hide, you're ready for permanent hair color. Our Nice n Easy Color Blend Foam is great for someone who's coloring their hair for the first time. I tell people to put the foam in their hands, rub it into their hands, and then massage it into your scalp and then pull it out through the tips. When it touches the natural oils of the hair, it collapses into a liquid, so it distributes evenly and is pretty fool proof.

And once you use it once, unless you were exposed to harsh elements like the sun or chlorine, you can generally just retouch the roots from there on out. Then after your retouch application, you run it through to the ends for the last couple minutes to refresh and to give it shine.

There are demi-permanents, like Natural Instincts, that's meant for someone who is 25% grey or less. It doesn't cover it permanently, it just blends it in and enhances your own natural highlight. The reds there are beautiful, the gold shades are nice. So they are good for a first-time user who doesn't want to go too extreme. And if grey isn't your issue, demi is a great way to go.

Glamour: For someone who dyed their hair too dark, or bleached their hair and it turned orange, can they fix it themselves?

Marie: No, if someone bleaches their hair or it comes out too light, do not fix it at home. I think that's something that the professionals should take care of. If you're talking about permanent hair color, it takes longer time to fade than semi-permanents. That's why people should always have stages, and then once you love it, stick with it. It's better than going extreme—that's the easiest way for someone to not be afraid to do it at home.

Glamour: Let's talk about gingers! Can everyone go red? Is there anyone who should absolutely just not try red?

Marie: A lot more people can go red than they realize, it's just the amount of lightness of red. There are two rules: if you are too pink in the skin, you get Rosacea or are naturally rosy, you want to be careful of shades that are too blue and red for you. So I find that they should use reds that are more strawberry, orange, brown-red and copper. If someone is olive or has yellow skin tone, be careful of those coppers. You can go a dark copper brown a chestnut or auburn, but if you go into middle ranges, your skin and hair will start looking the same.

Glamour: What's something hair color pros do in the salon that women should do at home?

Marie: I think this is where the ombre thing is great. For someone who has a nice long layered hair cut, you can take the foam and do an ombre color. You can go more than two shades more drastic because it's just the ends. Here's what you do: grab the product, grab sections of your hair starting at your mid-length, and pull it through the tips. And let it process the whole time.

Do you play it safe with hair or experiment? Would you (or do you?) try it at home? Tell us your best at-home dye tips and share your stories!